Always send the code from the client

Queue the execution request per kernel

conftest.py

@@ -7,6 +7,6 @@
 def jp_server_config(jp_server_config):
     return {
         "ServerApp": {
-            "jpserver_extensions": {"jupyter_server_nbmodel": True, "jupyter_server_ydoc": True}
+            "jpserver_extensions": {"jupyter_server_nbmodel": True, "jupyter_server_ydoc": False}
         }
     }

jupyter_server_nbmodel/extension.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import asyncio
+
 from jupyter_server.extension.application import ExtensionApp
 from jupyter_server.services.kernels.handlers import _kernel_id_regex
 
@@ -27,27 +29,31 @@ def initialize_handlers(self):
                 get_logger().warning("%i collaboration extensions found.", n_extensions)
             rtc_extension = next(iter(rtc_extensions))
 
-        self.__tasks = ExecutionStack()
+        self.__execution_stack = ExecutionStack(
+            manager=self.settings["kernel_manager"], ydoc_extension=rtc_extension
+        )
 
         self.handlers.extend(
             [
                 (
                     f"/api/kernels/{_kernel_id_regex}/execute",
                     ExecuteHandler,
-                    {"ydoc_extension": rtc_extension, "execution_stack": self.__tasks},
+                    {"execution_stack": self.__execution_stack},
                 ),
                 (
                     f"/api/kernels/{_kernel_id_regex}/input",
                     InputHandler,
+                    {"execution_stack": self.__execution_stack},
                 ),
                 (
                     f"/api/kernels/{_kernel_id_regex}/requests/{_request_id_regex}",
                     RequestHandler,
-                    {"execution_stack": self.__tasks},
+                    {"execution_stack": self.__execution_stack},
                 ),
             ]
         )
 
     async def stop_extension(self):
-        if hasattr(self, "__tasks"):
-            del self.__tasks
+        if hasattr(self, "__execution_stack"):
+            get_logger().info("Disposing the execution stack…")
+            await asyncio.wait_for(self.__execution_stack.dispose(), timeout=3)